During the first year of this study, 38 healthy volunteers were accrued as active granulocyte donors and donated a total of 105 filgrastim- and dexamethasone-stimulated granulocyte apheresis components. These were administered to 14 patients with severe neutropenia and life-threatening infections; the most common recipient diagnosis was severe aplastic anemia (n=7), followed by chronic granulomatous disease (n=4), acute leukemia (n=2) and non-Hodgkins lymphoma (n=1). Eight of 14 recipients had disseminated mold and six had life-threatening bacterial infections, including two with carbapenem-resistant Klebsiella pneumonia. A median of 5 granulocyte transfusions (range 1 to 29) were administered per patient course. Two patients did not respond to the granulocyte transfusions (GTX) and died rapidly, one assessed as a futile effort, and the other unable to receive a sustained course of GTX due to HLA alloimmunization and lack of compatible donors. The remaining 12 showed stability or clinical improvement, although 6 later died due to their underlying disease. Six of 14 were discharged from hospital. One recipient developed HLA alloimmunization due to GTX, which resulted in rejection of an unrelated cord blood graft. Donors experienced mild to moderate insomnia, nightmares, irritability and jitteriness related to the dexamethasone, and myalgia, arthralgias, fatigue and flushing related to the filgrastim administration. Twelve donors underwent comprehensive eye exams for cataract detection as a baseline assessment prior to repetitive dexamethasone administration. Donor retention in the program was 100%. A mean of 7.4 liters were processed per procedure, during which 6.89 x 10e10 granulocytes (range 3.82-20.61 x 10e10) were collected in a volume of 324 mL. Granulocyte collection efficiency was only 43% using the Spectra apheresis device, with WBC differential composed of 88% granulocytes, and with a mean hematocrit of 12% and a mean red cell content of 40 mL. Areas for further study or improvement include the low granulocyte collection efficiency of the Spectra apheresis device. A comparative efficacy study of the Spectra with the manufacturer's next generation cell separator, the Spectra Optia, will be performed as part of this study within the next year. New strategies to recruit additional committed granulocyte donors will be addressed in the next year in order to increase the study accrual numbers.